United Airlines will start using the Boeing 787 on domestic routes on May 20, USA Today reported on Wednesday. A flight from Houston to Chicago will be the airline's first flight for the jet since it was grounded by the FAA in mid-January, after two incidents when the airplane's lithium-ion batteries overheated. It's also the first flight announced for the jet on a U.S. route. Ethiopian Airlines and Qatar Airways already have resumed 787 service. The FAA has approved a modification that aims to both "prevent and isolate a fault should it occur," Boeing said. Meanwhile, the NTSB is continuing its investigation to try to determine why the batteries malfunctioned.

Air India is expected to resume 787 flights in mid-May, and to have all six of its 787s flying by early June, according to The Wall Street Journal. The approved fix requires operators to install new batteries and battery chargers, which are "designed to prevent cell failure and a battery overheat condition which can lead to a thermal event." Operators also must install a new battery enclosure and ducts that are designed to remove vented gases and contain a thermal event. The changes will add about 185 pounds to each aircraft. The full text of the Boeing service bulletin -- all 516 pages of it -- is posted online.